Rare causes of leg ulceration

Cause Appearance  Description 
Tuberculosis    
Pyoderma gangrenosum  
  • Undermined edte
  • Violaceous
  • Necrotic ulcer with hypertrophic margins 
Syphillis  
  • Gumma or tertiary syphilis has typical punched-out ulcer
  • Over anterior surface of lower leg and yellow coloured "wash leather" base
  • Scalloped border
Arteriovenous fistulae  
  • Ulcer distal to fistula
  • Shallow indolent ulcers
Rheumatoid arthritis  
  • Necrotising vasculitis
  • Purpuric, haemorrhagic bullae
Squamous cell carcinoma  
  • Rolled or raised edge
  • Often sun damaged skin
Sickle cell disease  
  • Small punched out ulcers
  • Often over medial aspect of lower leg